Silver nanoparticles effects on epididymal sperm in rats.

The motivation of our study was to examine the acute effects of intravenously administered a single bolus dose of silver nanoparticles (AgNPs) on rat spermatogenesis and seminiferous tubules morphology. In the treated rats compared to the vehicle treated control animals, the experiments revealed a size-dependent (20nm and 200nm), dose-dependent (5 and 10mg/kg body mass) and time-dependent (24h, 7 and 28days) decrease the epididymal sperm count measured by histological methods. In parallel AgNPs injection increased the level of DNA damage in germ cells, as measured by alkaline comet assay. Histological examination of the testes showed change in the testes seminiferous tubule morphometry in 200nm Ag NPs treated rats. No change of body weight, adipose tissue distribution and the frequency of abnormal spermatozoa was observed. Twenty nanometers AgNP appeared to be more toxic than 200nm ones.